extending life of trackpoint caps

[Paul Rubin <phr@netcom.com>]

I've discovered a neat trick for when the cap surface gets hard
and smooth.  I'd thought that was caused by the cats tongue surface
wearing off, meaning the cap needed to be replaced.  But it turns
out that the cap is just absorbing gunk from my fingertip which
dries and hardens.  Taking off the cap and rubbing it against my
pants leg like a pencil eraser, and picking out the gunk loosened
up by doing this, makes the cap usable for quite a bit longer.
(Eventually it does wear down).  Thought I'd pass this on.